What is the starting dose of Wegovy — and why does it begin so low?

Step 1: the first four weeks on 0.25 mg

The 0.25 mg starting dose exists almost entirely to ease your digestive system into treatment. At this level, most people notice little in the way of weight change, that is expected and normal. What the first pen is doing is giving your gut the chance to acclimatise before the dose climbs. Semaglutide activates GLP-1 receptors involved in appetite signalling and gastric emptying, and starting lower means the side effects that come from those mechanisms (nausea chief among them) tend to arrive more gently. The NHS medicines page for semaglutide confirms this graduated approach and notes that nausea, diarrhoea and constipation are most common in the first weeks of treatment or after a dose increase.

If you are feeling uncertain right now (reading this at midnight wondering whether a low starting dose means treatment is pointless) that doubt is genuinely understandable. The first pen can feel anticlimactic. It is not.

You inject once a week, rotating between the abdomen, thigh or upper arm. The day of the week is your choice; what matters is consistency. Your prescriber and the Patient Information Leaflet cover storage, injection technique and missed-dose guidance in detail, these are not decisions to improvise.

Step 2: titrating from 0.5 mg through 1.7 mg over the next three months

After four weeks at 0.25 mg, a prescriber who is satisfied with how you have tolerated treatment will typically move you to 0.5 mg for the next four weeks, then 1.0 mg, then 1.7 mg. Each rung of the ladder covers roughly a month, so by the end of week sixteen most people following the standard schedule are approaching the penultimate dose. The gaps between increases are not arbitrary, they reflect how long the medicine takes to reach a new steady state in the body and how long side effects need to settle before adding more.

People sometimes ask whether they can skip ahead. That is a clinical decision, not a personal one. Some people genuinely tolerate dose increases faster; others need longer at a particular level. A prescriber reviewing your progress is far better placed to judge this than a general guide. If you are curious about what the evidence says on starting at a higher level, our page on starting Wegovy at a higher dose covers what the SmPC and clinical guidance actually permit, and we also have specific guidance on whether starting Wegovy at 1 mg is something a prescriber might consider in your situation.

Side effects through this period are GI-led: nausea, loose stools, indigestion and reduced appetite are most frequently reported. They are often mild, tend to be temporary, and are far more likely to cause the odd miserable day than any lasting problem. Serious reactions (severe abdominal pain that spreads to the back, signs of an allergic response) need prompt medical attention. Report anything unexpected to your prescriber or via the MHRA Yellow Card scheme.

Step 3: reaching 2.4 mg, the standard maintenance dose

After roughly four weeks at 1.7 mg, most people step up to the 2.4 mg maintenance dose. This is where the bulk of the clinical evidence sits. In the STEP 1 trial, participants using semaglutide 2.4 mg weekly alongside lifestyle support achieved an average weight reduction of around 15% over 68 weeks. That is the figure worth keeping in mind when you are injecting 0.25 mg in week one and wondering whether the slow start is worth it, and if you have been asking yourself whether starting at 1mg rather than the standard dose is an option, that page explains what the clinical evidence actually supports.

For a fuller look at all the dose stages and what the licensed schedule covers, the complete Wegovy dose guide goes through each level in more detail. If cost is a factor in your thinking, the Wegovy price comparison sets out what private treatment typically costs in the UK and what a legitimate price should include.

The MHRA approved a higher 7.2 mg maintenance dose for Wegovy in January 2026, with a dedicated single-dose pen approved in April 2026 for adults with a BMI of 30 or above. This is a newer option, whether it forms part of your treatment is a decision made with your prescriber based on your response to 2.4 mg, not something to seek from day one.

What a prescriber looks at before week one even begins

Before the 0.25 mg starting dose is dispensed, a prescriber reviews your full health picture. Wegovy is licensed for adults with a BMI of 30 or above, or 27 or above alongside at least one weight-related condition such as high blood pressure, raised cholesterol or obstructive sleep apnoea. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance. Pregnancy, breastfeeding, a personal or family history of medullary thyroid carcinoma, and certain gastrointestinal conditions are among the factors that would make treatment unsuitable, the prescriber's job is to work through all of this, not just tick a BMI box.

At nume, every consultation is reviewed the same day by a GPhC-registered Independent Prescriber, a real clinician reads your answers before anything is prescribed or dispensed. You can read more about how we approach clinical oversight on our about us page, or explore Wegovy treatment at nume if you would like to understand the full service before committing to anything. When you are ready, starting your free consultation is the natural next step.